Nautilus vs Frontier for puzzling w/ Radian

[aja]

posting this for a friend:

We currently own a Blvd (for DS3) that expires in a year and a Radian (for DD5), plus a Keyfit (DS1) that will be outgrown in a few months. I need to purchase a different seat for someone this fall and then another seat next year when the Blvd expires.

I'm looking at Nautilus (we have one in Dh's car) or Frontier and wondering which would fit better with the Radian if we needed to put all 3 in the 3rd row. So it would either be Nautilus/Radian/Nautilus or Frontier/Radian/Frontier - either as harnessed seats or in booster mode for the outer seats.

Does that question make sense? I'm just trying to make the most out of our purchase. I know the Frontier has a slightly higher harness limit. I would like to choose the one that will fit best in the combinations mentioned above.

 

[aja]

oh, and it's the third row of a 2010 odyssey.

 

[mylittlet]

Highly doubt a nautilus, radian, nautilus would work. That is a very wide combination. The nautilus are not 3 across friendly. What other seats are in the car? Ages, weights and torso heights of kids?